It really depends on how you define "important". In the context of college football (where few things are actually "important", but where we all nonetheless invest enormous emotion), and even more specifically, Colorado's program within the broader boundaries of college football, I would consider a "W" somewhat important.
This is why...
CU's success lies in recruiting quality athletes capable of taking this team to the next level. CU doesn't need to be national champions to attract that kind of talent, but simply demonstrate a positive trend. Simply put, Coach Hawk's teams must exceed expectations to recruit in the short-term.
In year one, Coach Hawkins' team underachieved, but he got a free-pass for obvious reasons. Last year CU overachieved and was rewarded in recruiting. This year we've met expectations (general expectations, though not always our own expectations as fans). A victory against KSU would go a long way to show that we're heading in the right direction.
If CU underachieves, as evidenced by a loss against KSU, it could potentially affect this year's class. What does that mean for long-term implications? Well, if we can't attract quality on the D-line or defensive secondary soon, CU may find itself in a hole. Realistically, however, when the injury bug levels and the team regains some of its academic casualties (come on guys...Simas...we need you to play!) this team will be good-to-excellent for the next three years. After that, recruiting should become somewhat self-perpetuating.
Though team success is only one component in recruiting, it's a fairly significant one, as it appeals to the young athlete's ego, and desire to be associated with a proven winner.
On a personal level, a KSU victory is very important for my emotional health.